Trouble Code Conditions

SPECIAL TOOLS
Test box tool No. 981 3190, or equivalent
Volvo scan tool No. 998 8686, or equivalent

CONDITION
Shift solenoids S2 and S1 operate in tandem to control gear-shifting. Solenoid S2 operates when it receives battery voltage from the Transmission Control Module (TCM) and is activated in reverse, 1st and 2nd gears. Diagnostic Trouble Code (DTC) AT-221 is posted if the TCM registers a short-circuit to ground in solenoid S2 circuit when the solenoid should not be activated. Solenoid S2 cannot be activated.

SUBSTITUTE VALUE
The TCM limp-home program has been initiated.

POSSIBLE SOURCE
- Short-circuit to ground in signal cable.
- Defective solenoid

FAULT SYMPTOM(S)
- The combined instrument panel warning lamp flashes.
- Deterioration in performance because the TCM prevents activation of the solenoids, this stops gear-shifting. The transmission operates only in 3rd gear in positions 3 and L, 4th gear in position D and reverse in position R. Shifting can only be carried out manually between 3rd, 4th, and reverse gear.
- No system pressure solenoid STH control resulting in constant maximum system pressure leading to harsher shifting and gear meshing.
- No lock-up function.

NOTE: The Motronic 4.4 ECM posts a DTC when the transmission sends a Malfunction Indicator Lamp (MIL) request. Erase this DTC in the Motronic ECM when the transmission fault has been repaired.

TESTING PROCEDURE
- Start fault-tracing at Short Circuit To Ground. Short-Circuit To Ground